A key feature of a video server is its ability to generate streams of video at a precise bit rate. This is critical for compliance with the Motion Picture Experts Group (MPEG) standard. A secondary goal for a video server is of-course, a low cost of its components. There is a conflict between these two goals, since cheaper components tend to have higher drift. This is particularly true of components such as crystals. Earlier video servers that do not utilize this invention required expensive, highly stable crystal oscillators to be included in their design.
Commonly available General Purpose Operating System software does not provide deterministic response times to events (such as the availability of data from a disk, or the need to output data at a given time). To solve these problems, two solutions are typically employed either together or singly. First, operating system software with deterministic behavior is utilized. This software has a premium cost associated with them in the form of runtime royalties and development seat costs. Second, custom hardware is designed to tackle the timing problems and the Operating system read/writes data to/from the hardware via a buffering system, separating the Operating system from the time critical constraints. Such hardware development and fabrication have costs and risks associated with them.